I try to upload a file in adobe creative cloud and get server error.

[#1]

Can't upload any files in creative cloud.  Get "server_error" blue box.

[#2]

Moving this discussion to the File Hosting, Syncing, and Collaboration forum.

[#3]

For what its worth i had this error in firefox, then i tried chrome and it worked..

[#4]

Try clearing the cache and cookies in Firefox and see if the error still happens.